Used BCG from Aim Surplus. Exact model specifications can be found here: http://www.aimsurplus.com/product.aspx?item=xaimbcgnibbdg
BCG has had exactly 80 rounds through it. I had it on a 300 BO upper and sold the upper separately so I no longer have a need for it.
$80 shipped in the CONUS. Prefer PayPal friends and family.